1. Field of the Invention
The present invention relates to a waterproof structure of a casing and, especially, to a waterproof structure that prevents moisture and dust from entering a casing from where a case body and a cover of the casing pivotally connect to each other.
2. Description of the Prior Art(s)
A smart card, such as a subscriber identity module (SIM) card, a memory card or the like, is inserted in a portable electronic device, such as a mobile phone, a tablet computer, a digital camera, a personal digital assistant (PDA) or the like, to allow the portable electronic device to read data stored in the smart card.
A conventional electronic device has a case body and a cover. The case body has a slot formed in the case body. The cover selectively covers the slot of the case body. Preferably, the cover has a pivot edge pivotally connected to the case body. Thus, when the cover pivots to reveal the slot, the smart card is capable of being inserted into the slot of the case body to connect with electronic elements in the conventional electronic device. Then the cover pivots reversely to cover the slot of the case body so the smart card is stored in the slot of the case body.
However, since the cover is pivotally mounted on the case body, a clearance of about 0.3 millimeter (mm) between the pivot edge of the cover and the case body has to be reserved to allow the cover to pivot relative to the case body. Thus, moisture and dust inevitably enter the case body through the clearance and damage the electronic elements inside the case body. Consequently, the conventional electronic device is unable to pass an electro static discharge (ESD) test.
To overcome the shortcomings, the present invention provides a waterproof structure of a casing to mitigate or obviate the aforementioned problems.